Hitch Terms Glossary

The ball attachment onto a hitch / hitch receiver where the trailer coupler is joined.

Ball Height

The distance from the center of the ball hitch or coupling to the ground while parked on a flat surface.

Ball Mount

The removable ball hitch platform that can be slide into a receiver and normally attaches with a clip or a pin. This supports the ball hitch and connects it to the trailer coupler.

BCW (Base Curb Weight)

The total weight of a standard vehicle including a full tank of fuel. This does not include passengers, cargo or vehicle add-ons.

Brake Controller

This unit is mounted inside your tow vehicle and allows the electric trailer brakes to activate at the same time your tow vehicles brakes activate. You can manually activate trailer brakes and adjust the trailer braking with this device.

Breakaway Switch

A safety switch that engages the trailers brakes if the trailer becomes disconnected from the hitch while traveling.

CW (Cargo Weight)

This includes all the weight added to the BCW (base curb weight). Therefore all passengers, cargo, non-standard equipment and TW (trailer tongue weight) has been included.

Coupler

The portion of the trailer tongue that attaches the tow vehicle to the hitch ball.

Curb Weight (Net Weight)

The weight of the vehicle or trailer without any additional cargo.

Drawbar

Sometimes referred to as a non-adjustable coupling system different than a ball hitch, this is a coupling platform that can be added and removed by sliding into a hitch receiver. It fastens with either a pin or a clip or in some instances, the tongue of a hitch.

DW (Dry Weight)

Also known as unloaded vehicle weight, this is the weight of your vehicle or RV without fuel, water, supplies, passengers or other options.

Dually

A pickup truck, or light-duty tow vehicle, with four tires on one rear axle.

Frame-Mount Hitch

Hitches designed to be bolted to the vehicle frame or cross members. These hitches are Class II, III, IV and V.

GAW (Gross Axle Weight)

The total weight of the vehicle’s axles and trailer’s axles combined. This number is normally arrived at by weighing your vehicle on a scale.

GAWR (Gross Axle Weight Rating)

The vehicle manufacturer’s rating for the maximum weight allowed per axle.

GCWR (Gross Combined Weight Rating)

The total allowed weight of the combination of tow vehicle and trailer/fifth-wheel, or motor-home and dinghy. This number also includes the weight of the vehicle, trailer/fifth-wheel (or dinghy), cargo, passengers and a full load of fluids (fresh water, propane, fuel, etc.).

GCVW (Gross Combined Vehicle Weight)

The total combined weight of the vehicle and trailer (or towing equipment). This includes passengers and cargo.

GCW (Gross Combined Weight)

The real actual weight of the vehicle and trailer combined. This number is arrived at by weighing the vehicle and trailer on a scale.

GTW (Gross Trailer Weight)

The weight of the trailer, fully loaded and in towing condition.

GVW (Gross Vehicle Weight)

Fully loaded vehicle weight. Or BCW + CW. This includes passengers.

GVWR (Gross Vehicle Weight Rating)

Your vehicle manufacturer’s total allowable weight. This includes cargo, passengers, fuel and any hitch additions.

Hitch Class Ratings

Each hitch is rated differently by their specific manufacturer denoting the amount of tongue weight and tow weight they are engineered to handle. To make things easier, ratings are sorted into classes.

Plug

The wiring used to connect the trailer to the tow vehicle.

Receiver

The hitch portion the allows the hitch bar or shank to be inserted. These are normally 1 ½ to 2 inches square.

Safety Chains

Chains attached to the tow vehicle and connected to the trailer A-frame or tongue while towing. These are installed in the event of an uncoupling or hitch ball failure. Install in a criss cross pattern and check that they are secure each time you tow.

Shank

The threaded portion of the trailer ball.

Spring Bar

This is a central component of a weight distribution system. They are and installed and tensioned to distribute the trailer tongue load to the tow vehicle front forward axle.

Sway Control Device

Like a shock absorber, this resists the back and forth movement caused by wind and passing vehicles.

Tandem Axle

Two axles (four wheels).

TW (Tongue Weight)

The amount of weight imposed on the hitch when the trailer is coupled. Also referred to as “hitch weight”. Tongue weight for a travel trailer can be 10-15 percent of overall weight; fifth-wheel hitch weight is usually 18-20 percent of the overall weight.

Tow Bar

A device that bolts onto a vehicle, allowing it to be towed with all four wheels on the ground.

Tow Ratings

The amount of maximum weight the manufacturer recommends can be safely towed by a vehicle. These ratings refer to the trailer weight, not size. Some tow ratings are specific enough to referral to length. These ratings are determined by manufacturer according to several criteria, including engine size, transmission, axle ratio, brakes, chassis, cooling systems and other special equipment.

Weight Carrying Hitch

Sometimes referred to as a dead-weight hitch. This refers to any hitch used without a weight-distribution system. Some hitches have separate capacities based on use with or without a weight-distribution system.

Weight Distribution System

The function of weight distribution hitches is to give you better control of your vehicle and load by spreading the trailer’s weight across the tongue of your trailer and tow vehicle, especially when you have heavier loads. This prevents jostling of your load during transit and an overall better driving experience while operating the tow vehicle. RealTruck’s weight distribution hitches are used in addition to a standard hitch.

Yaw

When a trailer begins to fish-tail or moves in a side-to-side motion. This swaying is normally caused by an improperly loaded trailer (e.g. too much weight towards the rear of the trailer), or external forces like wind.